6 Cast Bronze/Copper Recessed Pull Sash Lifts. I believe these are rare. They are by P. & F. Corbin. Marked on the back: Patd Apr 11 1882. (Reference: https://patentimages.storage.googleapis.com/c4/7a/f5/8d7d6e80fe248b/US263070.pdf.) Lovely rosette pattern. Very good condition: patina consistent with age. Please see photos as they constitute part of the description.